1. Field of the Invention
The invention relates in general to a digital communication technique, and more particularly, to a technique for determining a phase error of a communication signal.
2. Description of the Related Art
Phase-shift keying (PSK) is a modulation scheme that conveys data by changing or modulating a phase of a signal. Phase-shift keying is prevalent in the digital communication field as it has high data transmission efficiency. Based on the number of candidate phases in a constellation, phase-shift keying is further categorized into binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK) and 8-PSK, etc.
For a phase-shift keying communication system, an important task of a receiver is to determine a phase of a currently received signal. The receiver can only retrieve information carried by the received signal after the phase of the received signal is accurately determined. However, in a wireless communication system, interference may be present due to factors such as channel noise and circuit mismatching in the receiver; thus, accurately determining the signal phase has become a great challenge.